Lung cancer

Definition

Lung cancer is cancer that starts in the lungs.

The lungs are located in the chest. When you breathe, air goes through your nose, down your windpipe (trachea), and into the lungs, where it flows through tubes called bronchi. Most lung cancer begins in the cells that line these tubes.

Alternative Names

Causes

Lung cancer is the deadliest type of cancer for both men and women. Each year, more people die of lung cancer than of breast, colon, and prostate cancers combined.

Lung cancer is more common in older adults. It is rare in people under age 45.

Cigarette smoking is the leading cause of lung cancer. The more cigarettes you smoke per day and the earlier you started smoking, the greater your risk of lung cancer. There is no evidence that smoking low-tar cigarettes lowers the risk.

These symptoms can also be due to other, less serious conditions, so it is important to talk to your health care provider.

Exams and Tests

Lung cancer is often found when an x-ray or CT scan is done for another reason.

If lung cancer is suspected, the doctor will perform a physical exam and ask about your medical history. You will be asked if you smoke. If so, you'll be asked how much you smoke and for how long you have smoked. You will also be asked about other things that may have put you at risk of lung cancer, such as exposure to certain chemicals.

When listening to the chest with a stethoscope, the doctor may hear fluid around the lungs. This may suggest cancer.

Tests that may be done to diagnose lung cancer or see if it has spread include:

In most cases, a piece of tissue is removed from your lungs for examination under a microscope. This is called a biopsy. There are several ways to do this:

Bronchoscopy combined with biopsy

CT-scan-directed needle biopsy

Endoscopic esophageal ultrasound (EUS) with biopsy

Mediastinoscopy with biopsy

Open lung biopsy

Pleural biopsy

If the biopsy shows cancer, more imaging tests are done to find out the stage of the cancer. Stage means how big the tumor is and how far it has spread. Staging helps guide treatment and follow-up and gives you an idea of what to expect.

Treatment

Treatment for lung cancer depends on the type of cancer, how advanced it is, and how healthy you are:

Surgery to remove the tumor may be done when it has not spread beyond nearby lymph nodes.

Chemotherapy uses drugs to kill cancer cells and stop new cells from growing.

The above treatments may be done alone or in combination. Your doctor can tell you more about the specific treatment you will receive.

Support Groups

You can ease the stress of illness by joining a cancer support group. Sharing with others who have common experiences and problems can help you not feel alone.

Outlook (Prognosis)

How well you do depends mostly on how much the lung cancer has spread.

When to Contact a Medical Professional

Call your health care provider if you have symptoms of lung cancer, particularly if you smoke.

Prevention

If you smoke, now is the time to quit. If you are having trouble quitting, talk with your doctor. There are many methods to help you quit, from support groups to prescription medicines. Also, try to avoid secondhand smoke.